Brake hydraulic device for vehicle

ABSTRACT

Provided is a brake hydraulic device for a vehicle, including: a base body having a hydraulic pressure path for brake fluid formed therein; an electromagnetic valve; an electromagnetic coil; a pressure sensor; and a housing attached to the outer surface of the base body. The housing includes a peripheral wall part and an intermediate wall part partitioning a space inside the peripheral wall part into a front side and a rear side. A plurality of bus bars on the coil side to be electrically connected to the electromagnetic coil, and a plurality of bus bars on the sensor side to be electrically connected to the pressure sensor are embedded in the intermediate wall part. A hierarchy region where the bus bars on the coil side and the bus bars on the sensor side are positioned in a hierarchy state with each other in the front-rear direction is provided.

TECHNICAL FIELD

The present invention relates to a brake hydraulic device for a vehicle.

BACKGROUND ART

As to a master cylinder unit (a brake hydraulic device for a vehicle) tobe used in a brake system for a vehicle, there exists a device includinga master cylinder to convert an input to a brake operation element intothe brake hydraulic pressure, an electromagnetic valve to open and closea hydraulic pressure path disposed in a base body of the mastercylinder, an electromagnetic coil to drive the electromagnetic valve, apressure sensor to detect intensity of the hydraulic pressure of thebrake fluid in the hydraulic pressure path, and a housing having ahousing chamber for accommodating the electromagnetic valve, theelectromagnetic coil, and the pressure sensor (for example, refer to thepatent document 1).

PRIOR ART DOCUMENT Patent Document

-   Patent document 1: Unexamined Japanese patent publication No.    2007-099058

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

In the inside of the housing of the above-mentioned master cylinderunit, it is required to secure a space for accommodating bus barsextending from a connector projecting on the outer surface of thehousing to the electromagnetic coil or the pressure sensor as well as aspace for accommodating various kinds of electric parts. Since such ahousing is attached to the outer surface of the base body of the mastercylinder, the housing is required to be made small.

Therefore, it is an object of the present invention to provide a brakehydraulic device for a vehicle capable of miniaturizing and lighteningthe housing to be attached to the outer surface of the base body.

Means for Solving the Problem

In order to solve the problem, the present invention provides a brakehydraulic device for a vehicle, including:

a base body having a hydraulic pressure path for brake fluid formedtherein;

an electromagnetic valve which opens and closes the hydraulic pressurepath;

an electromagnetic coil which drives the electromagnetic valve;

a pressure sensor which detects intensity of the hydraulic pressure ofthe brake fluid in the hydraulic pressure path; and

a housing attached to an outer surface of the base body and having ahousing chamber for accommodating the electromagnetic valve, theelectromagnetic coil, and the pressure sensor.

The housing includes a peripheral wall part having openings formed on afront side and a rear side thereof and an intermediate wall partpartitioning a space inside the peripheral wall part into a front sideand a rear side, and the housing chamber is provided on the rear side ofthe intermediate wall part.

A plurality of bus bars on the coil side to be electrically connected tothe electromagnetic coil, and a plurality of bus bars on the sensor sideto be electrically connected to the pressure sensor are embedded in theintermediate wall part, and a region in which the bus bars on the coilside and the bus bars on the sensor side are positioned in a hierarchystate with each other in a front-rear direction, is provided.

According to this configuration, since there is provided a region inwhich the bus bars on the coil side and the bus bars on the sensor sideare positioned in a hierarchy state with each other in the front-reardirection in the intermediate wall part, different kinds of bus bars canbe densely disposed. Therefore, a space for accommodating bus bars canbe miniaturized, the design flexibility for disposing the bus bars canbe enhanced.

And it is preferable that at least one of two hierarchy regions isprovided in the intermediate wall part to densely dispose the bus bars.One hierarchy region is a hierarchy region on the coil side in which therespective bus bars on the coil side are positioned in a hierarchy statein the front-rear direction, and the other hierarchy region is ahierarchy region on the sensor side in which the respective bus bars onthe sensor side are positioned in a hierarchy state in the front-reardirection.

Furthermore, in a case where a hierarchy region on the coil side inwhich the respective bus bars on the coil side are positioned in ahierarchy state in the front-rear direction, and a hierarchy region onthe sensor side in which the respective bus bars on the sensor side arepositioned in a hierarchy state in the front-rear direction, areprovided in the intermediate wall part, it is preferable that thehierarchy region on the coil side and the hierarchy region on the sensorside are shifted from each other in a wide direction of the intermediatewall part to prevent the hierarchy regions of bus bars from becomingthick in the front-rear direction.

In a case where at least either respective bus bars of the respectivebus bars on the coil side and the respective bus bars on the sensor sideare positioned in a hierarchy state in the front-rear direction whilebeing shifted in a wide direction of the intermediate wall part, therespective bus bars can be held in the front-rear direction with holdingpins or the like even in a region where the respective bus bars arepositioned in a hierarchy state with each other or one another, so thatthe bus bars can be accurately positioned when the intermediate wallpart is molded.

In a case where three of the electromagnetic valves are accommodated inthe housing chamber in the brake hydraulic device for a vehiclementioned above, it is preferable that the three electromagnetic valvesare disposed so that an isosceles triangle is formed of line segmentseach of which connects the axis positions of the three electromagneticvalves on a wall surface of the intermediate wall part. According tothis configuration, the three electromagnetic valves and theelectromagnetic coils can be compactly accommodated in the housing.

Note that, in a case where the openings of the peripheral wall part areformed to be quadrangular, the electromagnetic valves can be disposed inthree corner portions of the four corner portions of the peripheral wallpart, so that a space in the housing can be effectively utilized.

Furthermore, it is preferable that the pressure sensor is positioned ona line to divide the apex angle of the isosceles triangle formed of theline segments each of which connects the axis positions of the threeelectromagnetic valves, into two equal angles.

Furthermore, it is preferable that the pressure sensor is positionedoutside the region surrounded by the line segments each of whichconnects the axis positions of the three electromagnetic valves on thewall surface of the intermediate wall part.

Moreover, in a case where two pressure sensors are accommodated in thehousing chamber, it is preferable that one of the two pressure sensorsis positioned inside a region surrounded by the line segments each ofwhich connects the axis positions of the three electromagnetic valvesand an axis position of the other of the two pressure sensors on thewall surface of the intermediate wall part.

According to these respective configurations, the three electromagneticvalves and a pressure sensor or pressure sensors can be disposed in thehousing in a compact and good balance state.

Furthermore, a necessary space for accommodating bus bars is small andthe design flexibility for disposing the bus bars is large, according tothe present invention, so the space to dispose the bus bars can besecured in the housing even if electromagnetic valves, electromagneticcoils, and a pressure sensor or pressure sensors are disposed in thehousing in a compact state.

In a case where at least one electromagnetic valve of the threeelectromagnetic valves is attached to the intermediate wall part whilebeing shifted from the other electromagnetic valves in a front-reardirection, in the brake hydraulic device for a vehicle mentioned above,the design flexibility of the layout of the hydraulic pressure path tobe formed in the base body can be enhanced.

Effect of the Invention

According to the brake hydraulic device for a vehicle of the presentinvention, since a necessary space for accommodating bus bars in thehousing can be miniaturized and the design flexibility for disposing thebus bars can be enhanced, the housing can be miniaturized and lightened.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a whole structure view showing a brake system for a vehicleusing a master cylinder unit of the present embodiment;

FIG. 2A is a side view of the master cylinder unit of the presentembodiment;

FIG. 2B is a view of the master cylinder unit of the present embodimentviewed from the forward side;

FIG. 3 is a side view of the inside of a housing of the presentembodiment viewed from the front side;

FIG. 4 is an exploded perspective view showing the housing, shutoffvalves and pressure sensors of the present embodiment;

FIG. 5 is a sectional view of the housing and the shutoff valves takenalong the line A-A shown in FIG. 3;

FIG. 6 is a view showing the relation of the positions of theelectromagnetic valves and the pressure sensors of the presentembodiment;

FIG. 7 is a perspective view of the inside of the housing of the presentembodiment viewed from the front side;

FIG. 8 is a side view showing a group of bus bars on the coil side and agroup of bus bars on the sensor side of the present embodiment;

FIG. 9 is a perspective view showing the group of bus bars on the coilside and the group of bus bars on the sensor side of the presentembodiment;

FIG. 10 is an exploded perspective view showing the group of bus bars onthe coil side and the group of bus bars on the sensor side of thepresent embodiment;

FIG. 11 is a side view showing the group of bus bars on the coil side ofthe present embodiment; and

FIG. 12 is a side view showing the group of bus bars on the sensor sideof the present embodiment.

MODE FOR CARRYING OUT THE INVENTION

An embodiment of the present invention will be described in detailappropriately with reference to Figures.

In the present embodiment, a case where a master cylinder unit being abrake hydraulic device for a vehicle of the present invention is appliedto a brake system A for a vehicle (vehicle-brake system A) shown in FIG.1 will be explained as an example.

The vehicle-brake system A shown in FIG. 1 includes both of a ByWire-type brake system which operates when a power plant (engine,electric motor, or the like) starts, and a hydraulic brake system whichoperates in emergency or when the power plant stops or in the like.

The vehicle-brake system A is provided with a master cylinder unit A1 togenerate the brake hydraulic pressure in accordance with the steppingforce to step down a brake pedal P (brake operation element), a motorcylinder unit A2 to generate the brake hydraulic pressure with the useof an electric motor (not shown), and a hydraulic pressure control unitA3 to support the stabilization of the movement of a vehicle.

The master cylinder unit A1, the motor cylinder unit A2, and thehydraulic pressure control unit A3 are constituted as respective units,and connected to one another through external pipes.

The vehicle-brake system A can be also installed in a hybrid vehicleusing also an electric motor, in a fuel cell electric vehicle and anelectric vehicle using only an electric motor as a power source, and inthe like, as well as in a vehicle using a power source of only an engine(internal combustion engine).

The master cylinder unit A1 has a tandem-type master cylinder 1, astroke simulator 2, a reservoir 3, shutoff valves 4, 5, 6, pressuresensors 7, 8, main hydraulic pressure paths 9 a, 9 b, communicationhydraulic pressure paths 9 c, 9 d, and a branch hydraulic pressure path9 e. The aforementioned parts are installed to a base body 10, and therespective hydraulic pressure paths 9 a to 9 e are formed in the basebody 10.

The master cylinder 1 is one to convert the stepping force for the brakepedal P into the brake hydraulic pressure, and has a first piston 1 adisposed on a bottom surface side of a first cylindrical bore 11 a, asecond piston 1 b connected to a push rod R, a first elastic member 1 caccommodated in a first pressure chamber 1 e formed between the bottomsurface of the first cylindrical bore 11 a and the first piston 1 a, anda second elastic member 1 d accommodated in a second pressure chamber 1f formed between both of the pistons 1 a, 1 b.

The second piston 1 b is connected to the brake pedal P through the pushrod R. The both pistons 1 a, 1 b slide in the first cylindrical bore 11a in accordance with the stepping force for the brake pedal P, so thatthose pressurize brake fluid in the both pressure chamber 1 e, 1 f. Themain hydraulic pressure paths 9 a, 9 b communicate with the bothpressure chambers 1 e, 1 f, respectively.

The stroke simulator 2 is one to generate a pseudo-operational reactionforce for the brake pedal P, and has a piston 2 a capable of sliding ina second cylindrical bore 11 b, and two elastic members 2 b, 2 c urgingthe piston 2 a toward a bottom surface side.

The stroke simulator 2 is communicated with the first pressure chamber 1e of the master cylinder 1 through the branch hydraulic pressure path 9e and the main hydraulic pressure path 9 a, so that the piston 2 aoperates in accordance with the brake hydraulic pressure generated inthe first pressure chamber 1 e.

The reservoir 3 is a vessel to reserve the brake fluid therein, and hasfluid-supply ports 3 a, 3 b to be communicated with the master cylinder1, and a hose extending from a main reservoir (not shown) is connectedthereto.

The main hydraulic pressure paths 9 a, 9 b are hydraulic pressure pathsstarting from the master cylinder 1. Tubular members Ha, Hb which reachthe hydraulic pressure control unit A3 are connected to output ports 15a, 15 b positioned at the terminal points of the main hydraulic pressurepaths 9 a, 9 b.

The communication hydraulic pressure paths 9 c, 9 d are hydraulicpressure paths which reach the main hydraulic pressure paths 9 a, 9 bfrom input ports 15 c, 15 d. Tubular members Hc, Hd which reach themotor cylinder unit A2 are connected to the input ports 15 c, 15 d.

The branch hydraulic pressure path 9 e is a hydraulic pressure pathwhich branches from the main hydraulic pressure path 9 a communicatingwith the first pressure chamber 1 e and reaches the stroke simulator 2.

The first shutoff valve 4 and the second shutoff valve 5 are normallyopen type shutoff valves to open or close the main hydraulic pressurepaths 9 a, 9 b. The first shutoff valve 4 and the second shutoff valve5, as shown in FIG. 4, have electromagnetic valves 4 a, 5 a, andelectromagnetic coils 4 b, 5 b wound on the outside of theelectromagnetic valves 4 a, 5 a. And when current is supplied to theelectromagnetic coils 4 b, 5 b so that the electromagnetic coils 4 b, 5b are excited, the electromagnetic valves 4 a, 5 a are closed by movingof movable cores in the electromagnetic valves 4 a, 5 a.

As shown in FIG. 1, the first shutoff valve 4 opens or closes the mainhydraulic pressure path 9 a in the path between the crossing of the mainhydraulic pressure path 9 a and the branch hydraulic pressure path 9 eand the crossing of the main hydraulic pressure path 9 a and thecommunication hydraulic pressure path 9 c. And the second shutoff valve5 opens or closes the main hydraulic pressure path 9 b on the upstreamside of the crossing of the main hydraulic pressure path 9 b and thecommunication hydraulic pressure path 9 d.

The third shutoff valve 6 is a normally closed type shutoff valve toopen or close the branch hydraulic pressure path 9 e. The third shutoffvalve 6 has an electromagnetic valve 6 a and an electromagnetic coil 6 bwound on the outside of the electromagnetic valve 6 a as shown in FIG.4. And when current is supplied to the electromagnetic coil 6 b so thatthe electromagnetic coil 6 b is excited, the electromagnetic valve 6 ais opened by moving of a movable core in the electromagnetic valve 6 a.

Pressure sensors 7, 8 shown in FIG. 1 are ones to detect the intensityof the brake hydraulic pressure, are attached in sensor attachment holes(not shown) communicating with the main hydraulic pressure paths 9 a, 9b.

The first pressure sensor 7 is disposed on the downstream side of thefirst shutoff valve 4, and detects the brake hydraulic pressuregenerated in the motor cylinder unit A2 when the first shutoff valve 4is in the closed state (when the main hydraulic pressure path 9 a is inthe shut state).

The second pressure sensor 8 is disposed on the upstream side of thesecond shutoff valve 5, and detects the brake hydraulic pressuregenerated in the master cylinder 1 when the second shutoff valve 5 is inthe closed state (when the main hydraulic pressure path 9 b is in theshut state).

Data detected by the pressure sensors 7, 8 are output to an electroniccontrol unit not shown.

The master cylinder unit A1 is communicated with the hydraulic pressurecontrol unit A3 through the tubular members Ha, Hb. Therefore, the brakehydraulic pressures generated in the master cylinder 1 when the firstshutoff valve 4 and the second shutoff valve 5 are in the open state,are input into the hydraulic pressure control unit A3 through the mainhydraulic pressure paths 9 a, 9 b and the tubular members Ha, Hb.

The motor cylinder unit A2 has a slave piston to slide in a slavecylinder, an actuator mechanism having an electric motor and adriving-force-transmission part, and a reservoir to reserve the brakefluid in the slave cylinder, which are not shown.

The electric motor operates in accordance with signals from theelectronic control unit not shown. The driving-force-transmission parttransmits rotational power of the electric motor to the slave pistonafter converting the rotational power into forward-backward motion. Theslave piston slides in the slave cylinder in accordance with thereceived driving force of the electric motor to pressurize the brakefluid in the slave cylinder.

The brake hydraulic pressure generated in the motor cylinder unit A2 isinput into the master cylinder unit A1 through the tubular members Hc,Hd, and input into the hydraulic pressure control unit A3 through thecommunication hydraulic pressure paths 9 c, 9 d and the tubular membersHa, Hb. A hose extending from the main reservoir (not shown) isconnected to the reservoir.

The hydraulic pressure control unit A3 includes a constitution so as toexecute an antilock brake control (ABS control) to control slips ofwheels, a skid control to stabilize movement of a vehicle, a tractioncontrol, and the like, and is connected to wheel cylinders W throughtubular members.

Furthermore, the hydraulic pressure control unit A3 has a hydraulicpressure unit having an electromagnetic valve, a pump, and the like, anelectric motor to drive the pump, an electronic control unit to controlthe electromagnetic valve, the motor, and the like, which parts are notshown.

An outline of the operation of the vehicle-brake system. A will beexplained in the following.

In a normal time when the vehicle-brake system A normally operates, thefirst shutoff valve 4 and the second shutoff valve 5 are closed, and thethird shutoff valve 6 is opened.

When the brake pedal P is operated in this state, brake hydraulicpressure generated in the master cylinder 1 is not transmitted to thewheel cylinders W, but is transmitted to the stroke simulator 2, so thata stroke of the brake pedal P is allowed in accordance with displacementof the piston 2 a and the pseudo-operational reaction force is appliedto the brake pedal P.

When depression of the brake pedal P is detected by a stroke sensor orthe like not shown, the electric motor of the motor cylinder unit A2 isdriven, so that the brake fluid in the slave cylinder is pressurized inaccordance with displacement of the slave piston.

The electronic control unit not shown compares a brake hydraulicpressure output out of the motor cylinder unit A2 (a brake hydraulicpressure detected by the pressure sensor 7) with a brake hydraulicpressure output out of the master cylinder 1 (a brake hydraulic pressuredetected by the pressure sensor 8) to control a rotational speed and thelike of the electric motor based on the result of the comparison.

The brake hydraulic pressure generated in the motor cylinder unit A2 istransmitted to each wheel cylinder W through the hydraulic pressurecontrol unit A3, so that the braking force is applied to each wheel bythe operation of each wheel cylinder W.

Note that, when the motor cylinder unit A2 does not operate (forexample, when electric power is not got, in emergency, or the like),both of the first shutoff valve 4 and the second shutoff valve 5 becomeopen, and the third shutoff valve 6 becomes closed, so that the brakehydraulic pressure generated in the master cylinder 1 is transmitted tothe wheel cylinders W.

Next, the specific structure of the master cylinder unit A1 will beexplained.

The master cylinder unit A1 of the present embodiment is formed byinstalling aforementioned various parts in the inside or the outer sideportion of the base body 10 shown in FIGS. 2A and 2B, and by coveringparts to electrically operate (shutoff valves 4, 5, 6 and pressuresensors 7, 8) with a housing 20.

The base body 10 is a casting of aluminum alloy, and has a cylinder part11, a vehicle-body-fixing part 12, a reservoir-attachment part 13, ahousing-attachment part 14, and a pipe-connection part 15. And bores(not shown) being the main hydraulic pressure path 9 a, 9 b, the branchhydraulic pressure path 9 e (refer to FIG. 1), and the like are formedin the inside of the base body 10.

The first cylindrical bore 11 a of the master cylinder 1 and the secondcylindrical bore 11 b of the stroke simulator 2 are formed in thecylinder part 11.

Parts constituting the master cylinder 1 are inserted in the firstcylindrical bore 11 a, and parts constituting the stroke simulator 2 areinserted in the second cylindrical bore 11 b.

The vehicle-body-fixing part 12 is a part to be fixed to a vehicle bodylike a toe board, and is formed on the back face portion of the basebody 10.

The reservoir-attachment part 13 is a seat part to attach the reservoir3 thereto, and is formed on the upper face portion of the base body 10.And two reservoir union ports (not shown) are formed in thereservoir-attachment part 13.

The pipe-connection part 15 is a seat part to attach pipes thereto, andis formed on the forward face portion of the base body 10. Two outputports 15 a, 15 b and two input ports 15 c, 15 d are formed in thepipe-connection part 15.

The tubular members Ha, Hb extending to the hydraulic pressure controlunit A3 (refer to FIG. 1) are connected to the output ports 15 a, 15 b,and tubular members Hc, Hd extending to the motor cylinder unit A2(refer to FIG. 1) are connected to the input ports 15 c, 15 d.

The housing-attachment part 14 is a seat part to attach the housing 20thereto, and is formed on the side face portion of the base body 10. Thehousing-attachment part 14 presents a form of flange.

An upper end portion and a lower end portion of the housing-attachmentpart 14 overhang the top and the bottom of the cylinder part 11,respectively, and are formed with screw holes.

Three valve-attachment holes and two sensor-attachment holes are formedin the housing-attachment part 14, which holes are not shown. Theshutoff valves 4, 5, 6 are attached to the three valve-attachment holes,and the pressure sensors 7, 8 are attached to the two sensor-attachmentholes (refer to FIG. 5).

The housing 20 is a plastic box body. As shown in FIG. 4, the housing 20has a peripheral wall part 30 opened on the front side and the rearside, a cover 31 (refer to FIG. 5) to close an opening 30 a on the frontside of the peripheral wall part 30, a flange part 32 projecting from anouter surrounding edge part for an opening 30 b on the rear side of theperipheral wall part 30, two connectors 33, 34 disposed in projectingstate on the peripheral wall part 30, an intermediate wall part 40disposed inside the peripheral wall part 30, and a group 50 of bus barson the coil side and a group 60 of bus bars on the sensor side embeddedin the intermediate wall part 40 (refer to FIG. 8).

The peripheral wall part 30 is apart to surround parts attached to thehousing-attachment part 14 (refer to FIG. 5) (the shutoff valves 4, 5,6, and the pressure sensors 7, 8), and the contour thereof is formed tobe schematically quadrangular.

As shown in FIG. 5, the cover 31 is a cover to tightly close the opening30 a on the front side of the peripheral wall part 30, and is fixed onan end surface on the front side of the peripheral wall part 30 by meansof adhesion or welding.

The flange part 32 is a part to be crimped (or press-bonded) to thehousing-attachment part 14. Bolt-insertion holes 32 a (refer to FIG. 3)are formed in four corner portions of the flange part 32 correspondinglyto the screw holes of the housing-attachment part 14. Bolts 16 insertedin the bolt-insertion holes 32 a are screwed into the screw holes of thehousing-attachment part 14, so that the housing 20 is fixed to thehousing-attachment part 14.

Furthermore, an endless seal member 32 b is set on an end surface on therear side of the flange part 32 to tightly contact with thehousing-attachment part 14.

As shown in FIG. 4, the connectors 33, 34 have tubular forms withrectangular cross sections, and project from a forward surface of theperipheral wall part 30 with an adequate distance in the upper-lowerdirection.

The connector 33 on the coil side disposed on the upper side is aconnector to be connected with cables for supplying currents to theelectromagnetic coils 4 b, 5 b, 6 b.

The connector 34 on the sensor side disposed on the lower side is aconnector to be connected with cables for sending the detected signalsoutput from the pressure sensors 7, 8 to the electric control unit notshown.

The intermediate wall part 40 is a partition wall for partitioning aspace inside the peripheral wall part 30 into the front side and therear side, as shown in FIG. 5. The intermediate wall part 40 is formedto be substantially quadrangular (refer to FIG. 3), and a corner portion40 d on the back and lower side is offset toward the front side than theother portions. That is, the corner portion 40 d on the back and lowerside of the intermediate wall part 40 is, on the front surface 40 a,projected toward the front side than the other portions, and on the rearsurface 40 b, recessed toward the front side than the other portions.

A housing chamber 35 which accommodates the three shutoff valves 4, 5, 6and the two pressure sensors 7, 8 is formed on the rear side of theintermediate wall part 40 as shown in FIG. 4.

Three electromagnetic-valve-insertion holes 41, 42, 43, three openings41 a, 42 a, 43 a for coils, and two openings 44, 45 for sensors areformed through the intermediate wall part 40 in the front-rear directionas shown in FIG. 3.

The first electromagnetic-valve-insertion hole 41 is a tubular holeformed in a corner portion 40 c on the back and upper side of theintermediate wall part 40. An upper end portion of the electromagneticvalve 4 a of the first shutoff valve 4 is inserted into the firstelectromagnetic-valve-insertion hole 41 (refer to FIG. 5).

The first opening 41 a for coil is formed under the firstelectromagnetic-valve-insertion hole 41, into which opening a connectionterminal 4 c of the electromagnetic coil 4 b of the first shutoff valve4 is inserted.

The second electromagnetic-valve-insertion hole 42 is a tubular holeformed in the corner portion 40 d on the back and lower side of theintermediate wall part 40. An upper end portion of the electromagneticvalve 5 a of the second shutoff valve 5 is inserted into the secondelectromagnetic-valve-insertion hole 42 (refer to FIG. 5).

The second opening 42 a for coil is formed over the secondelectromagnetic-valve-insertion hole 42, into which opening a connectionterminal 5 c of the electromagnetic coil 5 b of the second shutoff valve5 is inserted.

The third electromagnetic-valve-insertion hole 43 is a tubular holeformed in a corner portion 40 e on the forward and lower side of theintermediate wall part 40. An upper end portion of the electromagneticvalve 6 a of the third shutoff valve 6 is inserted into the thirdelectromagnetic-valve-insertion hole 43.

The third opening 43 a for coil is formed over the thirdelectromagnetic-valve-insertion hole 43, into which opening a connectionterminal 6 c of the electromagnetic coil 6 b of the third shutoff valve6 is inserted.

In the present embodiment, on the front surface 40 a of the intermediatewall part 40, a line segment L1 connecting an axis position of theelectromagnetic valve 4 a of the first shutoff valve 4 and an axisposition of the electromagnetic valve 5 a of the second shutoff valve 5is directed in the upper-lower direction along a back edge portion ofthe peripheral wall part 30, as shown in FIG. 6.

Next, on the front surface 40 a of the intermediate wall part 40, a linesegment L2 connecting an axis position of the electromagnetic valve 5 aof the second shutoff valve 5 and an axis position of theelectromagnetic valve 6 a of the third shutoff valve 6 is directed inthe forward-back direction along a lower edge portion of the peripheralwall part 30.

Furthermore, the line segments L1 and L2 are orthogonally crossed toeach other at the axis position of the electromagnetic valve 5 a of thesecond shutoff valve 5, and have the same length.

Thus, the three electromagnetic-valve-insertion holes 41, 42, 43 aredisposed so that an isosceles triangle having an apex angle P1 at theaxis position of the electromagnetic valve 5 a of the second shutoffvalve 5 is formed of the line segments L1, L2, L3 connecting the axispositions of the three electromagnetic valves 4 a, 5 a, 6 a on the frontsurface 40 a of the intermediate wall part 40.

Furthermore, distances among the three electromagnetic-valve-insertionholes 41, 42, 43 are set so that adjacent electromagnetic coils amongthe electromagnetic coils 4 b, 5 b, 6 b are positioned with a prescribeddistance when the shutoff valves 4, 5, 6 are inserted into the threeelectromagnetic-valve-insertion holes 41, 42, 43, respectively.

The first opening 44 for sensor is open in the central portion 40 g ofthe intermediate wall part 40 as shown in FIG. 3. The second pressuresensor 8 is disposed on the rear side of a schematically central portionof the first opening 44 for sensor, so that four connection terminals 8a equipped on the second pressure sensor 8 are inserted into the firstopening 44 for sensor.

The second opening 45 for sensor is open in the forward and upper region40 f of the intermediate wall part 40. The first pressure sensor 7 isdisposed on the rear side of a schematically central portion of thesecond opening 45 for sensor, so that four connection terminals 7 aequipped on the first pressure sensor 7 are inserted into the secondopening 45 for sensor.

In the present embodiment, on the front surface 40 a of the intermediatewall part 40, the first opening 44 for sensor and the second opening 45for sensor are disposed so that the second pressure sensor 8 ispositioned on the line L4 which divides the apex angle P1 of theisosceles triangle into two equal angles on the front surface 40 a ofthe intermediate wall part 40, as shown in FIG. 6, which triangle isformed of the line segments L1, L2, L3 connecting the axis positions ofthe three electromagnetic valves 4 a, 5 a, 6 a.

And the first opening 44 for sensor is disposed so that the secondpressure sensor 8 is positioned outside the region of the isoscelestriangle surrounded by the line segments L1, L2, L3 on the front surface40 a of the intermediate wall part 40.

Furthermore, the first opening 44 for sensor and the second opening 45for sensor are disposed so that the second pressure sensor 8 ispositioned within a region in a quadrangle surrounded by (the) linesegments L1, L2, L5, L6 connecting the axis positions of the threeelectromagnetic valves 4 a, 4 b, 4 c and the axis position of the firstpressure sensor 7 on the front surface 40 a of the intermediate wallpart 40.

Recessed portions 46, 48 are formed around the firstelectromagnetic-valve-insertion hole 41 and the thirdelectromagnetic-valve-insertion hole 43, and a projecting portion 47 isformed around the second electromagnetic-valve-insertion hole 42 on thefront surface 40 a of the intermediate wall part 40 as shown in FIG. 7.

The recessed portion 46 formed around the firstelectromagnetic-valve-insertion hole 41 is a portion formed by reducingthe thickness of the wall on the front surface 40 a side when theintermediate wall part 40 is formed.

The recessed portion 46 is formed in a region adjacent to the peripheralwall part 30 (the region over and the region outside the back side ofthe first electromagnetic-valve-insertion hole 41) so as to avoid busbars 51, 52 on the coil side embedded in the intermediate wall part 40as shown in FIG. 8.

The recessed portion 46 is provided with a plurality of ribs 46 aextending in radial directions starting from the hole wall of the firstelectromagnetic-valve-insertion hole 41 toward the outside of the firstelectromagnetic-valve-insertion hole 41, and a rib 46 b formed along thecircular direction of the first electromagnetic-valve-insertion hole 41at an outside position apart from the hole wall of the firstelectromagnetic-valve-insertion hole 41 as shown in FIG. 7. And therecessed portion 46 is divided into a plurality of regions byintersecting of the ribs 46 a and the rib 46 b.

The recessed portion 48 formed around the thirdelectromagnetic-valve-insertion hole 43 is a portion formed by reducingthe thickness of the wall on the front surface 40 a side when theintermediate wall part 40 is formed.

The recessed portion 48 is formed in a region adjacent to the peripheralwall part 30 (the region outside the forward side of, the region under,and the region outside the back side of the thirdelectromagnetic-valve-insertion hole 43) so as to avoid bus bars 53, 54on the coil side embedded in the intermediate wall part 40 as shown inFIG. 8.

The recessed portion 48 is provided with a plurality of ribs 48 aextending in radial directions starting from the hole wall of the thirdelectromagnetic-valve-insertion hole 43 toward the outside of the thirdelectromagnetic-valve-insertion hole 43, and a rib 48 b formed along thecircular direction of the third electromagnetic-valve-insertion hole 43at an outside position apart from the hole wall of the thirdelectromagnetic-valve-insertion hole 43 as shown in FIG. 7. And therecessed portion 48 is divided into a plurality of regions byintersecting of the ribs 48 a and the rib 48 b.

The projecting portion 47 is formed of a plurality of ribs 47 a, 47 bprojecting on the front surface 40 a in the corner portion 40 d on theback and lower side of the intermediate wall part 40. Furthermore, thecorner portion 40 d on the back and lower side is offset toward thefront side than the other portions, so ribs 47 a, 47 b are formed byreducing the thickness of the peripheral portion outside the secondelectromagnetic-valve-insertion hole 42 when the intermediate wall part40 is formed.

The projecting portion 47 is formed in a region adjacent to theperipheral wall part 30 (the region outside the forward side of, theregion under, and the region outside the back side of the secondelectromagnetic-valve-insertion hole 42) so as to avoid bus bars 51, 52on the coil side embedded in the intermediate wall part 40 as shown inFIG. 8.

The projecting portion 47 is provided with a plurality of ribs 47 aextending in radial directions starting from the hole wall of the secondelectromagnetic-valve-insertion hole 42 toward the outside of the secondelectromagnetic-valve-insertion hole 42, and ribs 47 b formed along thecircular direction of the second electromagnetic-valve-insertion hole 42at outside positions apart from the hole wall of the secondelectromagnetic-valve-insertion hole 42 as shown in FIG. 7. And theprojecting portion 47 is divided into a plurality of regions byintersecting of the ribs 47 a and the ribs 47 b.

In the present embodiment, the group 50 of bus bars on the coil side andthe group 60 of bus bars on the sensor side are embedded in theintermediate wall part 40 through molding as shown in FIG. 8.

In FIG. 8, dots are plotted on the group 50 of bus bars on the coil sideto easily distinguish the group 50 of bus bars on the coil side from thegroup 60 of bus bars on the sensor side.

The group 50 of bus bars on the coil side is formed of four bus bars 51to 54 on the coil side extending from the connector 33 on the coil sideto the respective electromagnetic coils 4 b, 5 b, 6 b (refer to FIG. 3)as shown in FIG. 11.

The respective bus bars 51 to 54 on the coil side are conductive membersto supply currents to the respective electromagnetic coils 4 b, 5 b, 6 b(refer to FIG. 3) from cables connected to the connector 33 on the coilside.

In FIG. 11, dots are plotted on the two bus bars 51, 52 on the coil sideto easily distinguish the four bus bars 51 to 54 on the coil side.

The first bus bar 51 on the coil side is a conductive member on thecathode side. A terminal 51 a on the connector side is formed at one endthereof, and terminals 51 b, 51 c on the coil side are formed at theother ends branched into two as shown in FIG. 10. The terminal 51 a onthe connector side projects in the connector 33 on the coil side asshown in FIG. 2B.

Furthermore, the terminal 51 a on the connector side of the first busbar 51 on the coil side does not appear in FIG. 11, because it is hiddenon the rear side of a terminal 53 a on the connector side of the thirdbus bar 53 on the coil side to be described later.

The first bus bar 51 on the coil side extends from the connector 33 onthe coil side, through a region over the second opening 45 for sensorand a region between the first opening 44 for sensor and the firstelectromagnetic-valve-insertion hole 41, to regions outside the forwardsides of the first opening 41 a for coil and the second opening 42 a forcoil as shown in FIG. 11.

A terminal 51 b on the coil side of the first bus bar 51 on the coilside projects in the forward and upper region of the first opening 41 afor coil, and a terminal 51 c on the coil side projects in the forwardand lower region of the second opening 42 a for coil.

The second bus bar 52 on the coil side is a conductive member on theanode side. A terminal 52 a on the connector side is formed at one endthereof, and terminals 52 b, 52 c on the coil side are formed at theother ends branched into two as shown in FIG. 10. The terminal 52 a onthe connector side projects in the connector 33 on the coil side asshown in FIG. 2B, and is positioned over the upper side of the terminal51 a on the connector side.

Furthermore, the terminal 52 a on the connector side of the second busbar 52 on the coil side does not appear in FIG. 11, because it is hiddenon the rear side of a terminal 54 a on the connector side of the forthbus bar 54 on the coil side to be described later.

The second bus bar 52 on the coil side extends from the connector 33 onthe coil side, through a region over the second opening 45 for sensorand a region between the first electromagnetic-valve-insertion hole 41and the first opening 41 a for coil, to the regions outside the backsides of the first opening 41 a for coil and the second opening 42 a forcoil as shown in FIG. 11.

A terminal 52 b on the coil side of the second bus bar 52 on the coilside projects in the back and upper region of the first opening 41 a forcoil, and a terminal 52 c on the coil side projects in the back andlower region of the second opening 42 a for coil.

The first bus bar 51 on the coil side and the second bus bar 52 on thecoil side are formed of one metallic plate by punching, and are disposedschematically parallel to each other with a distance in the widthdirection. The first bus bar 51 on the coil side is disposed on thecenter side of the intermediate wall part 40, and the second bus bar 52on the coil side is disposed on the side of the peripheral wall part 30.

The third bus bar 53 on the coil side is a conductive member on theanode side. A terminal 53 a on the connector side is formed at one endof the third bus bar, and a terminal 53 b on the coil side is formed atthe other end as shown in FIG. 10. The terminal 53 a on the connectorside projects in the connector 33 on the coil side, and is positioned onthe front side of the terminal 51 a on the connector side as shown inFIG. 2B.

The third bus bar 53 on the coil side extends from the connector 33 onthe coil side, through a region over the second opening 45 for sensorand a region between the first opening 44 for sensor and the firstopening 41 a for coil, to the region under the third opening 43 a forcoil as shown in FIG. 11.

The terminal 53 b on the coil side of the third bus bar 53 on the coilside projects in the back and lower region of the third opening 43 a forcoil.

The forth bus bar 54 on the coil side is a conductive member on thecathode side. The terminal 54 a on the connector side is formed at oneend of the forth bus bar, and a terminal 54 b on the coil side is formedat the other end as shown in FIG. 10. The terminal 54 a on the connectorside projects in the connector 33 on the coil side, and is positioned onthe front side of the terminal 52 a on the connector side as shown inFIG. 2B.

The fourth bus bar 54 on the coil side extends from the connector 33 onthe coil side, through a region over the second opening 45 for sensorand a region between the first opening 44 for sensor and the firstopening 41 a for coil, to the region under the third opening 43 a forcoil as shown in FIG. 11.

The terminal 54 b on the coil side of the fourth bus bar 54 on the coilside projects in the forward and lower region of the third opening 43 afor coil.

The third bus bar 53 on the coil side and the fourth bus bar 54 on thecoil side are formed of one metallic plate by punching, and are disposedschematically parallel to each other with a distance in the widthdirection. The third bus bar 53 on the coil side is disposed on thecenter side of the intermediate wall part 40, and the fourth bus bar 54on the coil side is disposed on the side of the peripheral wall part 30.

There is provided a hierarchy region S1 on the coil side in a regionover the second opening 45 for sensor of the intermediate wall part 40.In the hierarchy region S1 on the coil side, the third bus bar 53 on thecoil side and the fourth bus bar 54 on the coil side are positioned overthe front sides of the first bus bar 51 on the coil side and the secondbus bar 52 on the coil side. That is, in the hierarchy region S1 on thecoil side, the embedded positions of the first bus bar 51 on the coilside and the second bus bar 52 on the coil side are shifted in thethickness direction of the intermediate wall part 40 with reference tothe embedded positions of the third bus bar 53 on the coil side and thefourth bus bar 54 on the coil side.

Furthermore, in the hierarchy region S1 on the coil side, the respectivebus bars 51 to 54 on the coil side are positioned in a hierarchy statein the front-rear direction with one another while being shifted in thewidth direction of the intermediate wall part 40 with one another. Thatis, the respective bus bars 51 to 54 on the coil side are disposed sothat the majorities of the first bus bar 51 on the coil side and thesecond bus bar 52 on the coil side can be seen when the hierarchy regionS1 on the coil side is seen from the front side like FIG. 11.

Bent portions 51 d to 54 d bent toward the front side are formed in backportions of the respective bus bars 51 to 54 on the coil side positionedmore posterior than the hierarchy region S1 on the coil side.

With regard to the respective bus bars 51 to 54 on the coil side,portions from the bent portions 51 d to 54 d to the respective terminals51 b, 52 b, 53 b, 54 b on the coil side are disposed on a plane parallelto the front surface 40 a of the intermediate wall part 40, and arejuxtaposed with distances in the width direction of the intermediatewall part 40.

In the region between the first opening 44 for sensor and the firstopening 41 a for coil, the third bus bar 53 on the coil side and thefourth bus bar 54 on the coil side are disposed nearer the center of theintermediate wall part 40 than the first bus bar 51 on the coil side andthe second bus bar 52 on the coil side.

With regard to the first bus bar 51 on the coil side and the second busbar 52 on the coil side, bent portions 51 e, 52 e bent toward the frontside are formed between the terminals 51 b, 52 b on the coil side andthe terminals 51 c, 51 b on the coil side.

With regard to the first bus bar 51 on the coil side and the second busbar 52 on the coil side, portions disposed around the second opening 42a for coil are shifted toward the front side with reference to portionsdisposed around the first opening 41 a for coil, and are disposed on aplane parallel to the front surface 40 a.

Furthermore, the respective terminals 51 b, 51 c, 52 b, 52 c, 53 b, 54 bon the coil side of the bus bars 51 to 54 on the coil side are benttoward the front side at right angles (refer to FIG. 7).

The group 60 of bus bars on the sensor side is formed of six bus bars 61to 66 on the sensor side extending from the connector 34 on the sensorside to the both pressure sensors 7, 8 (refer to FIG. 3) as shown inFIG. 12.

The respective bus bars 61 to 66 on the sensor side are conductivemembers to transfer detected signals output from the both pressuresensors 7, 8 to cables connected to the connector 34 on the sensor side.

Note that, in FIG. 12, dots are plotted on three bus bars 61, 62, 63 onthe sensor side to easily distinguish the respective bus bars 61 to 66on the sensor side.

The first bus bar 61 on the sensor side is the conductive member on theanode side. A terminal 61 a on the connector side is formed at one endof the first bus bar, and terminals 61 b, 61 c on the sensor side areformed at an intermediate portion and the other end as shown in FIG. 10.The terminal 61 a on the connector side projects in the connector 34 onthe sensor side as shown in FIG. 2B.

Note that, in FIG. 12, the terminal 61 a on the connector side of thefirst bus bar 61 on the sensor side does not appear because it is hiddenon the rear side of a terminal 64 a on the connector side of the fourthbus bar 64 on the sensor side to be described later.

The first bus bar 61 on the sensor side extends from the connector 34 onthe sensor side, through a region between the first opening 44 forsensor and the second opening 45 for sensor and the region between thefirst opening 44 for sensor and the first opening 41 a for coil to theregion under the first opening 44 for sensor as shown in FIG. 12.

The terminal 61 b on the sensor side of the first bus bar 61 on thesensor side projects in the back and lower region of the second opening45 for sensor, and the terminal 61 c on the sensor side projects in theback and lower region of the second opening 45 for sensor.

The second bus bar 62 on the sensor side is a conductive member totransfer a detected signal output from the pressure sensor 7, and aterminal 62 a on the connector side is formed at one end of the secondbus bar, and a terminal 62 b on the sensor side is formed at the otherend as shown in FIG. 10. The terminal 62 a on the connector sideprojects in the lower connector 34 and is disposed under the terminal 61a on the connector side as shown in FIG. 2B.

Note that, in FIG. 12, the terminal 62 a on the connector side of thesecond bus bar 62 on the sensor side does not appear because it ishidden on the rear side of a terminal 65 a on the connector side of afifth bus bar 65 on the sensor side to be described later.

The second bus bar 62 on the sensor side extends from the connector 34on the sensor side to the region under the second opening 45 for sensor,and the terminal 62 b on the sensor side projects in the forward andlower region of the second opening 45 for sensor as shown in FIG. 12.

The third bus bar 63 on the sensor side is a conductive member totransfer a detected signal output from the pressure sensors 8, and aterminal 63 a on the connector side is formed at one end of the thirdbus bar, and a terminal 63 b on the sensor side is formed at the otherend as shown in FIG. 10. The terminal 63 a on the connector sideprojects in the connector 34 on the sensor side and is disposed over theterminal 61 a on the connector side as shown in FIG. 2B.

Note that, in FIG. 12, the terminal 63 a on the connector side of thethird bus bar 63 on the sensor side does not appear because it is hiddenon the rear side of a terminal 66 a on the connector side of a sixth busbar 66 on the sensor side to be described later.

The third bus bar 63 on the sensor side extends from the connector 34 onthe sensor side, through regions outside the forward side of and overthe second opening 45 for sensor, to the region over the first opening44 for sensor, and the terminal 63 b on the sensor side projects in theforward and upper region of the first opening 44 for sensor as shown inFIG. 12.

The second bus bar 62 on the sensor side and the third bus bar 63 on thesensor side are formed of one metallic plate by punching. The second busbar 62 on the sensor side is disposed on the center side of theintermediate wall part 40, and the third bus bar 63 on the sensor sideis disposed on the side of the peripheral wall part 30.

The fourth bus bar 64 on the sensor side is a conductive member on thecathode side. A terminal 64 a on the connector side is formed at one endof the fourth bus bar, and terminals 64 b, 64 c on the sensor side areformed at an intermediate portion and the other end as shown in FIG. 10.The terminal 64 a on the connector side projects in the connector 34 onthe sensor side, and is disposed on the front side of the terminal 61 aon the connector side as shown in FIG. 2B.

The fourth bus bar 64 on the sensor side extends from the connector 34on the sensor side, through the region between the first opening 44 forsensor and the second opening 45 for sensor, to branch out into two, andextends to regions over the first opening 44 for sensor and the secondopening 45 for sensor as shown in FIG. 12. The terminal 64 b on thesensor side projects in the forward and upper region of the firstopening 44 for sensor, and the terminal 64 c on the sensor side projectsin the forward and upper region of the second opening 45 for sensor.

The fifth bus bar 65 on the sensor side is a conductive member totransfer a detected signal output from the second pressure sensor 8, anda terminal 65 a on the connector side is formed at one end of the fifthbus bar, and a terminal 65 b on the sensor side is formed at the otherend as shown in FIG. 10. The terminal 65 a on the connector sideprojects in the connector 34 on the sensor side and is disposed on thefront side of the terminal 62 a on the connector side as shown in FIG.2B.

The fifth bus bar 65 on the sensor side extends from the connector 34 onthe sensor, through the region between the second opening 45 for sensorand the third opening 43 a for coil, to the region under the firstopening 44 for sensor as shown in FIG. 12. The terminal 65 b on thesensor side projects in the forward and lower region of the firstopening 44 for sensor.

The sixth bus bar 66 on the sensor side is a conductive member totransfer a detected signal output from the first pressure sensor 7, anda terminal 66 a on the connector side is formed at one end of the sixthbus bar, and a terminal 66 b on the sensor side is formed at the otherend as shown in FIG. 10. The terminal 66 a on the connector sideprojects in the connector 34 on the sensor side and is disposed on thefront side of the terminal 63 a on the connector side as shown in FIG.2B.

The sixth bus bar 66 on the sensor side extends from the connector 34 onthe sensor side, through the region between the first opening 44 forsensor and the second opening 45 for sensor, to the region over thesecond opening 45 for sensor, and the terminal 66 b on the sensor sideprojects in the back and upper region of the second opening 45 forsensor as shown in FIG. 12.

The fourth bus bar 64 on the sensor side, the fifth bus bar 65 on thesensor side and the sixth bus bar 66 on the sensor side are formed ofone metallic plate by punching, and are disposed in the width directionwith distances. The sixth bus bar 66 on the sensor side is disposedabove the upper side of the fourth bus bar 64 on the sensor side, andthe fifth bus bar 65 on the sensor side is disposed below the lower sideof the fourth bus bar 64 on the sensor side.

In the region over the second opening 45 for sensor of the intermediatewall part 40, three bus bars 63, 64, 66 on the sensor side arepositioned over the front side of the hierarchy region S1 on the coilside where the respective bus bars 51 to 54 on the coil side arepositioned in a hierarchy state with one another, as shown in FIG. 8.

And there is provided a hierarchy region S2 on the sensor side in aregion near the connector 34 on the sensor side as shown in FIG. 12. Inthe hierarchy region S2 on the sensor side, the second bus bar 62 on thesensor side is positioned over the front side of the first bus bar 61 onthe sensor side, and moreover, the fourth bus bar 64 on the sensor side,the fifth bus bar 65 on the sensor side and the sixth bus bar 66 on thesensor side are positioned over the front sides of the second bus bar 62on the sensor side and the third bus bar 63 on the sensor side. That is,in the hierarchy region S2 on the sensor side, the embedded position ofthe first bus bar 61 on the sensor side, the embedded positions of thesecond bus bar 62 on the sensor side and the third bus bar 63 on thesensor side, and the embedded positions of the fourth bus bar 64 on thesensor side, the fifth bus bar 65 on the sensor side and the sixth busbar 66 on the sensor side, are shifted in the thickness direction of theintermediate wall part 40.

Furthermore, there is provided a hierarchy region S3 on the sensor sidein the region between the first opening 44 for sensor and the secondopening 45 for sensor of the intermediate wall part 40. In the hierarchyregion S3 on the sensor side, the fourth bus bar 64 on the sensor sideand the sixth bus bar 66 on the sensor side are positioned above thefront side of the first bus bar 61 on the sensor side. That is, in thehierarchy region S3 on the sensor side, the embedded position of thefirst bus bar 61 on the sensor side is shifted in the thicknessdirection of the intermediate wall part 40 with reference to theembedded positions of the fourth bus bar 64 on the sensor side and thesixth bus bar 66 on the sensor side.

Furthermore, there is provided a hierarchy region S4 on the sensor sidein the region over the upper side of the first opening 44 for sensor ofthe intermediate wall part 40. In the hierarchy region S4 on the sensorside, the third bus bar 63 on the sensor side is positioned over thefront side of the first bus bar 61 on the sensor side. That is, in thehierarchy region S4 on the sensor side, the embedded position of thefirst bus bar 61 on the sensor side is shifted in the thicknessdirection of the intermediate wall part 40 with reference to theembedded position of the third bus bar 63 on the sensor side.

Moreover, in each hierarchy region S2, S3, S4 on the sensor side, therespective bus bars 61 to 66 on the sensor side are positioned in ahierarchy state with one another in the front-rear direction of theintermediate wall part while being shifted in the width direction of theintermediate wall part 40. That is, the respective bus bars 61 to 66 onthe sensor side are disposed so that the majority area of each of thebus bars 61 to 66 on the sensor side can be seen when the hierarchyregions S2, S3, S4 on the sensor side are seen from the front side likeFIG. 12.

Furthermore, with regard to the fourth bus bar 64 on the sensor side,the fifth bus bar 65 on the sensor side and the sixth bus bar 66 on thesensor side, bended portions 64 d to 66 d bended toward the front sideare formed at positions between the terminals 64 a to 66 a on theconnector side and the hierarchy region S2 on the sensor side,respectively.

With regard to the fourth bus bar 64 on the sensor side, the fifth busbar 65 on the sensor side and the sixth bus bar 66 on the sensor side,portions from the bended portions 64 d to 66 d over to the respectiveterminals 64 b, 64 c, 65 b, 66 b on the sensor side are disposed on aplane parallel to the front surface 40 a of the intermediate wall part40, and juxtaposed in the width direction of the intermediate wall part40 with one another.

Furthermore, with regard to the first bus bar 61 on the sensor side, thesecond bus bar 62 on the sensor side and the third bus bar 63 on thesensor side, a plurality of bended portions are formed so that therespective terminals 61 b, 61 c, 62 b, 63 b on the sensor side aredisposed on the same plane that the terminals 64 b, 64 c, 65 b, 66 b onthe sensor side of the fourth bus bar 64 on the sensor side, of thefifth bus bar 65 on the sensor side and of the sixth bus bar 66 on thesensor side are disposed on, respectively.

Furthermore, as shown in FIG. 8, the hierarchy region S1 on the coilside where the respective bus bars 51 to 54 on the coil side arepositioned in a hierarchy state with one another in the front-reardirection and the hierarchy regions S2, S3, S4 on the sensor side wherethe respective bus bars 61 to 66 on the sensor side are positioned in ahierarchy state with one another in the front-rear direction, aredisposed so as to be shifted from one another in the width direction ofthe intermediate wall part 40. That is, as shown in FIG. 8, therespective hierarchy regions S1 to S4 are disposed so that those S1 toS4 can be seen when the group 50 of bus bars on the coil side and thegroup 60 of bus bars on the sensor side are viewed from the front side.

Furthermore, the respective terminals 61 b, 61 c, 62 b, 63 b, 64 b, 64c, 65 b, 66 b on the sensor side of the bus bars 61 to 66 on the sensorside are bended toward the front side at right angles (refer to FIG. 7).

Furthermore, the current value to flow in the respective bus bars 61 to66 on the sensor side is smaller than the current value to flow in therespective bus bars 51 to 54 on the coil side. So, the widths of theterminals 61 a to 66 a on the connector side of the bus bars 61 to 66 onthe sensor side are formed smaller than those of the terminals 51 a to54 a on the connector side of the bus bars 51 to 54 on the coil side.

As mentioned above, since the respective hierarchy regions S1 to S4 aredisposed in the intermediate wall part 40, a plurality of bus bars canbe formed in the narrow region between the upper edge portion of thesecond opening 45 for sensor and the peripheral wall part 30, and in thenarrow region between the first opening 44 for sensor and the secondopening 45 for sensor.

Note that, when the intermediate wall part 40 is formed, the respectivebus bars 51 to 54 on the coil side and the respective bus bars 61 to 66on the sensor side are assembled in the above-mentioned hierarchy statewith use of spacers made of resin, the respective bus bars 51 to 54 onthe coil side and the respective bus bars 61 to 66 on the sensor sidecan be molded in the intermediate wall part 40 together with thespacers.

As shown in FIG. 3, the two connection terminals 4 c provided to theelectromagnetic coil 4 b of the first shutoff valve 4 are inserted inthe first opening 41 a for coil, and the terminals 4 c are electricallyconnected to the terminals 51 b, 52 b on the coil side by means ofwelding or the like.

The two connection terminals 5 c provided to the electromagnetic coil 5b of the second shutoff valve 5 are inserted in the second opening 42 afor coil, and the terminals 5 c are electrically connected to theterminals 51 c, 52 c on the coil side by means of welding or the like.

The two connection terminals 6 c provided to the electromagnetic coil 6b of the third shutoff valve 6 are inserted in the third opening 43 afor coil, and the terminals 6 c are electrically connected to theterminals 53 b, 54 b on the coil side by means of welding or the like.

As shown in FIG. 5, elastic members 70 are disposed between the rearsurface 40 b of the intermediate wall part 40 and front surfaces of theelectromagnetic coils 4 b, 5 b, 6 b. The elastic members 70 are platesprings having the shapes of V in the side view, and for absorbingvibrations of the electromagnetic coils 4 b, 5 b, 6 b as well as pushingthe electromagnetic coils 4 b, 5 b, 6 b onto the base body 10.

As shown in FIG. 3, the four connection terminals 8 a equipped on thesecond pressure sensor 8 are inserted into the first opening 44 forsensor, and electrically connected to the terminals 61 c, 63 b, 64 b, 65b on the sensor side by means of welding or the like.

The four connection terminals 7 a equipped on the first pressure sensor7 are inserted into the second opening 45 for sensor, and electricallyconnected to the terminals 61 b, 62 b, 64 c, 66 b on the sensor side bymeans of welding or the like.

In the master cylinder unit A1 described above, as shown in FIG. 8,since the hierarchy region S1 on the coil side in which the respectivebus bars 51 to 54 on the coil side are positioned in a hierarchy statewith one another in the front-rear direction, and the hierarchy regionsS2 to S4 on the sensor side in which the respective bus bars 61 to 66 onthe sensor side are positioned in a hierarchy state with one another inthe front-rear direction, are disposed in the intermediate wall part 40,the respective bus bars are gathered densely. Furthermore, since thereexists the region in which the group 50 of bus bars on the coil side andthe group 60 of bus bars on the sensor side are positioned in ahierarchy state with each other in the front-rear direction in theintermediate wall part 40, different kinds of bus bars 51 to 54, and 61to 66 are gathered densely.

Accordingly, in the housing 20, the space to accommodate the bus bars 51to 54, 61 to 66 can be reduced, and the flexibility to dispose them 51to 54, 61 to 66 can be enhanced, so that the housing 20 can be formed tobe compact and light.

Note that, since the space to accommodate the bus bars 51 to 54, 61 to66 is small, and the flexibility to dispose them 51 to 54, 61 to 66 ishigh, the space to dispose the bus bars 51 to 54, 61 to 66 can besecured in the housing 20 also in the case where the three shutoffvalves 4, 5, 6 and the two pressure sensors 7, 8 are disposed compactlyin the housing 20.

Furthermore, since the hierarchy region S1 on the coil side and thehierarchy regions S2, S3, S4 on the sensor side are disposed so as to beshifted from one another in the width direction of the intermediate wallpart 40, the hierarchy regions of the bus bars 51 to 54, 61 to 66 can beprevented from being thick in the front-rear direction.

Furthermore, as shown in FIG. 6, the three shutoff valves 4, 5, 6 aredisposed so that the isosceles triangle is formed of the line segmentsL1, L2, L3 connecting the axis positions of the three electromagneticvalves 4 a, 5 a, 6 a on the front surface 40 a of the intermediate wallpart 40, thereby, the three shutoff valves 4, 5, 6 can be accommodatedcompactly in the housing 20.

Specifically, in the present embodiment, since the shutoff valves 4, 5,6 are disposed in three corner portions of the four corner portions ofthe peripheral wall part 30, the space in the housing 20 is efficientlyused.

Note that, the second pressure sensor 8 is positioned on the line L4which divides the apex angle P1 of the isosceles triangle formed of theline segments L1, L2, L3 into two equal angles. Furthermore, on thefront surface 40 a of the intermediate wall part 40, the second pressuresensor 8 is positioned within the region formed of the line segments L1,L2, L5, L6 connecting the axis positions of the three electromagneticvalves 4 a, 5 a, 6 a and the axis position of the first pressure sensor7, and outside the region of the isosceles triangle surrounded by theline segments L1, L2, L3. Thereby, the three shutoff valves 4, 5, 6 andthe two pressure sensors 7, 8 can be disposed compactly and in awell-balanced state in the housing 20.

Furthermore, as shown in FIGS. 11 and 12, in the hierarchy regions S1 toS4, the respective bus bars 51 to 54 on the coil side and the respectivebus bars 61 to 66 on the sensor side are positioned in a hierarchy statewith one another in the front-rear direction while being shifted fromone another in the width direction of the intermediate wall part 40.Therefore, the respective bus bars 51 to 54, 61 to 66 can be held in thefront-rear direction with holding pins or the like even in the regionswhere the respective bus bars 51 to 54, 61 to 66 are positioned in ahierarchy state with one another. Accordingly, the respective bus bars51 to 54, 61 to 66 can be precisely positioned when the intermediatewall part 40 is molded.

The flexibility of laying out the hydraulic pressure paths to be formedin the base body 10 can be enhanced by attaching the shutoff valves 4,5, 6 (refer to FIG. 3) to the intermediate wall part 40 in the state ofshifting the respective shutoff valves 4, 5, 6 in the front-reardirection as shown in FIG. 5.

Furthermore, since the recessed portions 46, 48 and the projectingportion 47 are formed on the front surface 40 a of the intermediate wallpart 40 as shown in FIG. 7 so that a surface area of the intermediatewall part 40 becomes large, the ability to dissipate the heat of theintermediate wall part 40 can be enhanced. And the strength of theintermediate wall part 40 can be increased while the thickness of theintermediate wall part 40 being kept not to become thick by forming therecessed portions 46, 48 and the projecting portion 47 on theintermediate wall part 40. Therefore, decrease of the strength of thehousing 20 due to heat can be prevented.

Furthermore, since the recessed portions 46, 48 and the projectingportion 47 are formed on the front surface 40 a of the intermediate wallpart 40, the elastic members 70 can be steadily received on the rearsurface 40 b of the intermediate wall part 40 (refer to FIG. 5), anddecrease of the strength of the intermediate wall part 40 due to thepressing forces of the elastic members 70 can be prevented.

Furthermore, the projecting portion 47 is constituted by the ribs 47 aformed to extend in radial directions, and there are provided the ribs48 a disposed to extend in radial directions in the recessed portions46, 48, so that the pressing forces of the elastic members 70 acted onthe intermediate wall part 40 can be effectively dispersed.

Furthermore, since the recessed portions 46, 48 are formed so as toavoid the bus bars 51 to 54, 61 to 66 embedded in the intermediate wallpart 40, the thickness of the intermediate wall part 40 can be kept notto become thick.

Furthermore, since the intermediate wall part 40, the recessed portions46, 48, and the projecting portion 47 are formed of resin material, therecessed portions 46, 48 and the projecting portion 47 can be moldedintegrally with the intermediate wall part 40.

The present embodiment has been described above, but the presentinvention is not limited to that embodiment and may be properly modifiedwithout departing from the purpose of the present invention.

For example, the number and/or the positions of the bus bars 51 to 54 onthe coil side and the bus bars 61 to 66 on the sensor side shown in FIG.8 are not limited to them, and can be properly set in accordance withthe number and/or the positions of electric parts in the housing 20.

Furthermore, in the present embodiment, the three shutoff valves 4, 5, 6and the two pressure sensors 7, 8 are accommodated in the housing 20,but the number and/or the positions are not limited to them. Andelectric parts to be accommodated in the housing 20 are not limited toshutoff valves and pressure sensors. For example, a substrate forcontrolling electric parts may be accommodated in the housing 20.

Furthermore, in the present embodiment, both of the hierarchy region S1on the coil side and the hierarchy regions S2 to S4 on the sensor sideare provided, but only either of the hierarchy region S1 on the coilside and the hierarchy regions S2 to S4 on the sensor side may beprovided. Additionally, neither the hierarchy region S1 on the coil sidenor the hierarchy regions S2 to S4 on the sensor side may be provided.

Furthermore, in the present embodiment, both of the recessed portions46, 48 and the projecting portion 47 are formed on the front surface 40a of the intermediate wall part 40, but it is all right that at leasteither of the recessed portions and the projecting portion is formed inaccordance with the strength and/or the ability to dissipate the heat ofthe intermediate wall part 40. Additionally, the configurations and/orthe positions of the recessed portions and the projecting portion arenot limited. And the recessed portions and the projecting portion may beformed on the rear surface of the intermediate wall part 40.

Furthermore, in the present embodiment, the recessed portions 46, 47 andthe projecting portion 47 of the intermediate wall part 40 are formed ofresin material and integrally with the intermediate wall part 40, butthe recessed portions and the projecting portion may be formed ofmetallic material, and may be molded with the intermediate wall part 40.

Furthermore, in the present embodiment, the case where the brakehydraulic device for a vehicle of the present invention is applied tothe master cylinder unit A1 of the vehicle-brake system A is explainedas an example, but a device or unit which the brake hydraulic device fora vehicle of the present invention can be applied to is not limited, andit can be also applied to a hydraulic pressure control unit to carry outan ABS control, a skid control, a traction control, or the like.

DESCRIPTION OF THE SYMBOLS

-   1 Master cylinder-   2 Stroke simulator-   3 Reservoir-   4 First shutoff valve-   4 a Electromagnetic valve-   4 b Electromagnetic coil-   5 Second shutoff valve-   5 a Electromagnetic valve-   5 b Electromagnetic coil-   6 Third shutoff valve-   6 a Electromagnetic valve-   6 b Electromagnetic coil-   7 First pressure sensor-   8 Second pressure sensor-   10 Base body-   20 Housing-   30 Peripheral wall part-   33 Connector on the coil side-   34 Connector on the sensor side-   35 Housing chamber-   40 Intermediate wall part-   41 First electromagnetic-valve-insertion hole-   41 a First opening for coil-   42 Second electromagnetic-valve-insertion hole-   42 a Second opening for coil-   43 Third electromagnetic-valve-insertion hole-   43 a Third opening for coil-   44 First opening for sensor-   45 Second opening for sensor-   46 Recessed portion-   46 a, 46 b Rib-   47 Projecting portion-   47 a, 47 b Rib-   48 Recessed portion-   48 a, 48 b Rib-   50 Group of bus bars on the coil side-   51 First bus bar on the coil side-   51 a Terminal on the connector side-   51 b, 51 c Terminal on the coil side-   52 Second bus bar on the coil side-   52 a Terminal on the connector side-   52 b, 52 c Terminal on the coil side-   53 Third bus bar on the coil side-   53 a Terminal on the connector side-   53 b Terminal on the coil side-   54 Fourth bus bar on the coil side-   54 a Terminal on the connector side-   54 b Terminal on the coil side-   60 Group of bus bars on the sensor side-   61 First bus bar on the sensor side-   61 a Terminal on the connector side-   61 b, 61 c Terminal on the sensor side-   62 Second bus bar on the sensor side-   62 a Terminal on the connector side-   62 b Terminal on the sensor side-   63 Third bus bar on the sensor side-   63 a Terminal on the connector side-   63 b Terminal on the sensor side-   64 Fourth bus bar on the sensor side-   64 a Terminal on the connector side-   64 b, 64 c Terminal on the sensor side-   65 Fifth bus bar on the sensor side-   65 a Terminal on the connector side-   65 b Terminal on the sensor side-   66 Sixth bus bar on the sensor side-   66 a Terminal on the connector side-   66 b Terminal on the sensor side-   70 Elastic member-   A Vehicle-brake system-   A1 Master cylinder unit-   A2 Motor cylinder unit-   A3 Hydraulic pressure control unit-   S1 Hierarchy region on the coil side-   S2, S3, S4 Hierarchy region on the sensor side

1. A brake hydraulic device for a vehicle, comprising: a base bodyhaving a hydraulic pressure path for brake fluid formed therein; anelectromagnetic valve which opens and closes the hydraulic pressurepath; an electromagnetic coil which drives the electromagnetic valve; apressure sensor which detects intensity of the hydraulic pressure of thebrake fluid in the hydraulic pressure path; and a housing attached to anouter surface of the base body and having a housing chamber foraccommodating the electromagnetic valve, the electromagnetic coil, andthe pressure sensor, wherein the housing includes a peripheral wall parthaving openings formed on a front side and a rear side thereof, and anintermediate wall part partitioning a space inside the peripheral wallpart into a front side and a rear side, wherein the housing chamber isprovided on the rear side of the intermediate wall part, wherein aplurality of bus bars on the coil side to be electrically connected tothe electromagnetic coil, and a plurality of bus bars on the sensor sideto be electrically connected to the pressure sensor are embedded in theintermediate wall part, and wherein a region in which the bus bars onthe coil side and the bus bars on the sensor side are positioned in ahierarchy state with each other in a front-rear direction, is provided.2. The brake hydraulic device for a vehicle according to claim 1,wherein at least one of two hierarchy regions is provided in theintermediate wall part, one hierarchy region being a hierarchy region onthe coil side in which the respective bus bars on the coil side arepositioned in a hierarchy state in the front-rear direction, and theother hierarchy region being a hierarchy region on the sensor side inwhich the respective bus bars on the sensor side are positioned in ahierarchy state in the front-rear direction.
 3. The brake hydraulicdevice for a vehicle according to claim 1, wherein a hierarchy region onthe coil side in which the respective bus bars on the coil side arepositioned in a hierarchy state in the front-rear direction, and ahierarchy region on the sensor side in which the respective bus bars onthe sensor side are positioned in a hierarchy state in the front-reardirection, are provided in the intermediate wall part, and wherein thehierarchy region on the coil side and the hierarchy region on the sensorside are shifted from each other in a wide direction of the intermediatewall part.
 4. The brake hydraulic device for a vehicle according toclaim 2, wherein at least either respective bus bars of the respectivebus bars on the coil side and the respective bus bars on the sensor sideare positioned in a hierarchy state in the front-rear direction whilebeing shifted in a wide direction of the intermediate wall part.
 5. Thebrake hydraulic device for a vehicle according to claim 1, wherein threeelectromagnetic valves each of which is the electromagnetic valve areaccommodated in the housing chamber, and wherein an isosceles triangleis formed of line segments each of which connects the axis positions ofthe three electromagnetic valves on a wall surface of the intermediatewall part.
 6. The brake hydraulic device for a vehicle according toclaim 5, wherein the pressure sensor is positioned on a line to dividethe apex angle of the isosceles triangle formed of the line segmentseach of which connects the axis positions of the three electromagneticvalves, into two equal angles.
 7. The brake hydraulic device for avehicle according to claim 5, wherein the pressure sensor is positionedoutside the region surrounded by the line segments each of whichconnects the axis positions of the three electromagnetic valves on thewall surface of the intermediate wall part.
 8. The brake hydraulicdevice for a vehicle according to claim 5, wherein two pressure sensorseach of which is the pressure sensor are accommodated in the housingchamber, and wherein one of the two pressure sensors is positionedinside a region surrounded by line segments each of which connects theaxis positions of the three electromagnetic valves and an axis positionof the other of the two pressure sensors on the wall surface of theintermediate wall part.
 9. The brake hydraulic device for a vehicleaccording to claim 5, wherein at least one electromagnetic valve of thethree electromagnetic valves is attached to the intermediate wall partwhile being shifted from the other electromagnetic valves in thefront-rear direction.
 10. The brake hydraulic device for a vehicleaccording to claim 3, wherein at least either respective bus bars of therespective bus bars on the coil side and the respective bus bars on thesensor side are positioned in a hierarchy state in the front-reardirection while being shifted in a wide direction of the intermediatewall part.
 11. The brake hydraulic device for a vehicle according toclaim 6, wherein the pressure sensor is positioned outside the regionsurrounded by the line segments each of which connects the axispositions of the three electromagnetic valves on the wall surface of theintermediate wall part.
 12. The brake hydraulic device for a vehicleaccording to claim 6, wherein two pressure sensors each of which is thepressure sensor are accommodated in the housing chamber, and wherein oneof the two pressure sensors is positioned inside a region surrounded byline segments each of which connects the axis positions of the threeelectromagnetic valves and an axis position of the other of the twopressure sensors on the wall surface of the intermediate wall part. 13.The brake hydraulic device for a vehicle according to claim 6, whereinat least one electromagnetic valve of the three electromagnetic valvesis attached to the intermediate wall part while being shifted from theother electromagnetic valves in the front-rear direction.